What major transportation initiative was established by the National Highway Act of 1956?

The National Highway Act of 1956 was significant because it established the Interstate Highway System, which transformed the landscape of American transportation and infrastructure. This initiative aimed to provide a comprehensive network of highways facilitating faster and more efficient travel across the country. It was inspired by the need for improved national defense and the increasing automobile culture, enabling the movement of troops and supplies in case of military emergencies, while also promoting economic growth and suburban expansion.

The Interstate Highway System dramatically reshaped American society by making long-distance travel and transportation of goods faster and easier, thereby influencing patterns of settlement and commerce. This initiative also contributed to the interconnectedness of urban and rural areas, further solidifying the automobile as a centerpiece of American life.

The other options refer to transportation initiatives that, while important, are not the result of the National Highway Act of 1956. The Urban Mass Transit System focuses on public transportation within cities, the Federal Aviation System concerns air travel and the management of aviation infrastructure, and a National Rail Network involves rail transport systems, which were not the direct focus of the legislation aimed specifically at roadways and highway construction.